This invention relates to an argricultural tool bar which is adapted to be pulled by a traction vehicle; and more particularly, it relates to a tool bar which is capable of being folded to the rear for road travel.
Typically, a tool bar of the type with which the present invention is concerned carries a number of individual implements, such as seed planters, chisel plows, ammonia knives, or other ground-working tools or devices. As used herein, "tool bar" refers to the overall apparatus or system, and a "tool support beam" is the horizontal member which extends transversely of the direction of travel of the vehicle in the use position and on which the individual devices are mounted.
In the illustrated embodiment, the devices mounted on the tool support beam are corn planters, so reference will be made throughout to such planters. However, persons skilled in the art will readily appreciate that many other individual devices may be readily incorporated into the present invention.
There has been a tendency in modern tractors to incorporate greater and greater power into the prime mover, resulting in increased drawbar pull. This can be accounted for, at least in part, by modern farming techniques which require deeper plowing of the soil. At any rate, with the power available, there has been a desire to incorporate greater numbers of planters, for example, on a tool bar. Realizing that the planters are spaced at row intervals, the width of such tool bars during use is substantial. For example, planters are available which are capable of simultaneously planting twelve 30-inch rows. The overall width of such a device is approximately 30 feet. The advantages of planting or cultivating twelve rows at a time are obvious. However, one commercial embodiment of a twelve-row planter has a rigid one-piece tool support beam, and it requires a separate trailer for transport over the road. The tool bar is loaded sideways onto the trailer. The time required for loading, unloading and connection at the planting site, together with the added expense of the separate long trailer, offsets many of the advantages of the wide tool bar.
In one commercial cultivator capable of cultivating eight rows of 30-inch spacing (again, too wide for road travel), the tool support beam is a rigid one-piece construction having a hitch at one end and a pair of support wheels at the other end so that the tool bar may be pulled lengthwise for road travel. Again, it is required that the farmer disconnect the use position of the tool bar from the tractor and re-connect the end hitch for road travel.
Folding tool bars have been suggested and are available. In one commercial embodiment, a cultivator capable of working twelve rows is divided into two side sections, one located on either side of the tractor body. The cultivator is specially mounted at the forward end of the tractor and for road travel, the two cultivator wings are folded forward, so that the outboard ends of the tool support beams in the use position are in front of the tractor and linked together in the road travel position.
Another folding tool bar which is available commercially has a rigid center section connected to the rear of a tractor and two outboard portions or wings which fold vertically by means of hydraulic cylinders which may be housed in the center beam, if desired. In this device, the width of the system in the folded position is not substantially less than it is in the extended or use position because even though the tool support beams are folded, they are folded in such a manner that the implements mounted to the beams extend outwardly in the folded position--thereby adding their height to the width of the apparatus in the travel position. Further, tool bars which fold vertically are undesirable for use with planters or liquid applicators because the seed boxes and chemicals with the planting units must be emptied to avoid spilling or leaking of the contents and to reduce the weight of the units to avoid bending damage.
A rear-mounted, forward-folding tool bar is disclosed in U.S. Pat. No. 3,491,836. In this patent, the three sections of the tool bar must be rotated so that the devices carried thereby extend vertically in the travel position (as contrasted to horizontally in the use position) prior to folding.
Rear-folding tool bars have also been suggested, although none are known to me which are capable of accommodating seed planters which do not have to be emptied in order to place the tool bar in the travel position. For example, one such rear-folding tool bar is disclosed in U.S. Pat. No. 3,548,954, but this device, like that disclosed in the previously-mentioned patent, requires that the various sections of the tool support beam be rotated about a common horizontal axis prior to folding so that the implements carried by it extend vertically. Other patents of interest include three U.S. Pat. Nos. 3,502,154, 3,637,027, and 3,774,693.
The present invention concerns an agricultural tool bar which includes a main frame adapted to be drawn by a traction vehicle. The main frame is independently supported by wheels, and it may be raised by means of a hydraulic cylinder and piston rod unit. The main frame includes a base member and cross frame member rigidly connected. Thus, in the illustrated embodiment, the main frame has a general T-shape with the cross frame member extending transverse of the direction of travel of the vehicle and the base of the T-shape being located generally along the center line of the system. The center line, of course, extends in the direction of travel of the vehicle.
First and second tool support beams extend laterally of the main frame and carry implements such as seed planters, chisel plows or the like. The inboard ends of the tool support beams in the illustrated embodiment are located adjacent each other in the use position, and the axes of these beams are collinear and extend transverse of the direction of travel of the vehicle.
A pair of side frame members connects the tool support beams respectively to the outboard ends of the cross frame member of the main frame for pivotal motion about respective vertical axes. Preferably, the cross frame member of the main frame is located at a higher elevation than the tool support beams. Thus, these side frame members just mentioned extend from the tool support beams upwardly and rearwardly to the outboard ends of the cross frame member. The tool support beams may be folded with their outboard ends being pivoted rearwardly about the connection of the side frame member to the cross frame member. In the folded position, the axes of the tool support beams extend parallel to the direction of travel of the vehicle, and the implements carried by the tool support beams are located within the perimeter of the beams in the folded position.
A pair of articulated links are provided, one for each tool support beam. The forward end of each articulated link is connected to the main frame at a forward position thereof, and the rear end of each link is connected to an intermediate position on the associated tool support beam. Each link includes a bending section or elbow. In the use position, the articulated links are folded, and the elbow of each link is secured to the associated tool support beam at a location outboard of the pivot location for the tool support beam. Thus, the tool support beam is stabilized in the extended or use position. When the tool support beam is folded rearwardly, the articulated link is extended, and the elbow is connected to the inboard end of the tool support beam to hold it in the folded position.
Each tool support beam may be provided with caster wheels at their outboard ends for support in the folded position. In the use position, additional support wheels may be provided, and these two sets of wheels may be raised and lowered hydraulically by the operator without leaving his position in the seat of the tractor.
In operation, the apparatus of the present invention is simple. To fold the tool support beams for road travel, the operator raises the main frame by actuating a first hydraulic cylinder and piston rod unit. He then lowers the caster wheels while raising the other support wheels for each tool support beam. At the same time, any row markers provided on the outboard ends of the tool support beams are raised. This may all be done with controls located adjacent the operator's position and without having to move from that position. The operator then unlatches the elbows of the articulated links and simply drives forward a short distance. The outboard ends of the tool support beams, supported now by the caster wheels, are free to move rearwardly and do so until the apparatus assumes the travel position, at which time, the elbows of the articulated links latch to the inboard ends of the tool support bars which are now located in forward positions. The apparatus is thus set up for road travel, all of the implements having been raised, but not tilted or otherwise turned, by raising the main frame and by lowering the caster wheels.
In order to set up the apparatus for use at the working site, the operator simply reverses the procedure just mentioned--that is, first he unlatches the elbows of the articulated links from the inboard or forward ends of the tool support bars, and he then drives the tractor in reverse circling first to one side and then to the other until the two side tool support beams are latched in the use position. The planters may then be lowered for planting by raising the caster wheels and by lowering the main frame.
It will thus be appreciated that the present invention provides a tool bar system which readily folds between the use position and the travel position. Further, because of the structure, the tool support beams may be extended to cover a large number of rows. For example, the present invention could readily be extended to have an overall width (in the use position) of 75 feet or more, and yet be folded to the travel position having an overall width of about 16 feet, and thus easily pulled along a highway.
Further, it will be appreciated that folding of the tool bar may be accomplished with a minimum of effort by the operator and in a very short time, but with a little experience. Folding does not require that the tool support beams or the implements carried by it be twisted or turned in any manner so the apparatus is suitable for use with many different types of tools, devices or implements.